Method for manufacturing wire electrical discharge machining device

Abstract

To provide a method for manufacturing a wire electrical discharge device reducing variation in machining dimension for each device to improve reproducibility of the machining dimension.SOLUTION: A method for producing a wire electrical discharge device comprises an adjustment process adjusting an output voltage waveform of a switching element by changing a resistance value of a resistor when supplying an adjusting voltage pulse generated by a pulse generation circuit or a pulse generation device to a gate signal generation circuit. The electrical discharge machining device includes: a pulse generation circuit outputting a voltage pulse for controlling the switching element to the gate signal generation circuit using a differential system; a gate signal generation circuit the signal input route of which is provided with a resistor and which is provided with a photo coupler receiving a differential voltage pulse and outputting the pulse to the switching driver, and the switching driver generating the gate signal; and a bipolar circuit supplying the voltage pulse whose polarity is periodically switched, to a machining gap by control of the switching element by the gate signal.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a wire electric discharge machining apparatus. [Background technology]

[0002] 2. Description of the Related Art Wire electric discharge machining apparatuses are known that apply a voltage between a wire and a workpiece to generate a discharge current between the wire and the workpiece, thereby cutting the workpiece.

[0003] Patent Document 1 discloses a wire electric discharge machining apparatus that can achieve stable quality and machining performance by adjusting the electrode voltage between the wire and the workpiece and controlling the electrode distance between the wire and the workpiece. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-202606 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the midst of demands for more stable quality and machining performance, it has become possible to machine fine surface roughness at high speed by increasing the frequency of the electrode gap voltage pulse between the wire and the workpiece. However, in wire EDM using high-frequency pulses, a phenomenon occurs in which minute changes in pulse width caused by individual differences in the threshold voltage of the electric element T present in the transmission path of the discharge pulse accumulate and appear in the electrode gap pulse width of the final stage. This phenomenon causes machine differences, which is a major factor that inhibits the reproducibility of machining performance in the machining condition database that specifies the state of the discharge pulse.

[0006] A voltage pulse that can be treated as a square wave in the low frequency range actually has a transition region where the voltage rises and falls. Therefore, in the high frequency range, the nature of a trapezoidal wave becomes evident. The electric element T that transmits the discharge pulse has a threshold voltage V th The threshold voltage V of the electrical element T th In many cases, the specifications allow for an individual difference of about 1V. th Due to individual differences in the input pulse, there will be a difference in the timing of the rising and / or falling edge of the output pulse relative to the input pulse. As a result, the input pulse width T in and output pulse width T out However, different phenomena occur for each wire EDM machine.

[0007] For example, the input peak voltage V peak 1 / 2 of the threshold voltage V of the electrical element T th If the reference value is set to , the threshold voltage V of the electrical element T is th is the input peak voltage V peak If the output pulse width is higher than 1 / 2, out is the input pulse width T in The threshold voltage V th is the input peak voltage V peak If the output pulse width is less than half of T out is the input pulse width T in It will be longer than that (Figure 1).

[0008] In other words, the input pulse width T in Even if the reference threshold voltage V Rth (hereinafter, the reference threshold voltage) than the threshold voltage V th When is high, the reference output pulse width T Rout Output pulse width T out The reference threshold voltage V Rth than the threshold voltage V th When is low, the reference output pulse width T Rout Output pulse width T outIn general voltage settings, the former threshold voltage V th is the reference threshold voltage V Rth Therefore, the discharge pulse has a pulse width of T out The reduction in length accumulates and tends to get shorter with each stage.

[0009] Therefore, the input pulse width T in Even if the threshold voltage V of each electrical element T is the same, th Due to individual differences, the output pulse width T out This results in differences in the final discharge pulse width even for circuits with the same specifications. And because the discharge pulse width and the electric discharge machining energy are proportional, the electric discharge machining conditions differ for each device, even for devices of the same model. Due to this effect, even if the machining performance of a single wire electric discharge machining device is improved, there will be variation in the machining results even when machining is performed under the same machining conditions for each mass-produced wire electric discharge machining device, and the reproducibility of the machining dimensions for each device will be low. Therefore, there was a problem specific to wire electric discharge machining using high-frequency pulses, in that it was difficult to improve the machining dimensional accuracy of the entire machining condition database.

[0010] The present invention has been made in view of the above circumstances, and aims to reduce the threshold voltage V th The final stage pulse width T out This eliminates the difference between the above two, thereby providing a method for manufacturing a wire electric discharge machining apparatus that can reduce the variation in machining dimensions and improve the reproducibility of the machining dimensions. [Means for solving the problem]

[0011] According to the present invention, the following inventions are provided. [1] A method for manufacturing a wire electric discharge machining device including a pulse generating circuit, a gate signal generating circuit, and a bipolar circuit, wherein the pulse generating circuit outputs a voltage pulse for controlling a switching element of the bipolar circuit to the gate signal generating circuit in a differential manner, the gate signal generating circuit includes a photocoupler and a switching driver, the photocoupler receives a differential voltage pulse from the pulse generating circuit and outputs it to the switching driver, the switching driver generates a gate signal for driving the switching element, the bipolar circuit is a bridge circuit having the switching element on each side, the switching element is controlled by receiving the gate signal, and an inter-machine voltage pulse whose polarity periodically switches is supplied to a machining gap between a wire and a workpiece, the photocoupler includes a resistor in a signal input path, and the manufacturing method includes an adjustment step, in which an output voltage waveform of the switching element when an adjustment voltage pulse generated by the pulse generating circuit or an external pulse generating device is supplied to the gate signal generating circuit is adjusted by changing a resistance value of the resistor. [2] A method for manufacturing a wire electric discharge machining device as described in [1], comprising: performing the adjustment step in a state in which a substrate having the gate signal generating circuit and the bipolar circuit is supplied with the adjustment voltage pulse by the external pulse generating device independent of the wire electric discharge machining device; and comprising an assembly step of assembling the substrate into the wire electric discharge machining device after the adjustment step. [3] A method for manufacturing a wire electric discharge machining device according to the item [1] or [2], wherein the switching element is a field effect transistor, and in the adjustment step, a pulse width of a voltage waveform between a source and a drain of the field effect transistor is kept within a predetermined range. Effect of the Invention

[0012] In the method for manufacturing a wire electric discharge machining device according to the present invention, when an adjustment voltage pulse generated by a pulse generating circuit or an external pulse generating device is supplied to a gate signal generating circuit, the resistance value of a resistor provided in a signal input path of a photocoupler provided in the gate signal generating circuit is changed.By including an adjustment step for adjusting the output voltage waveform of a switching element provided in a bipolar circuit, it is possible to correct variations in the machining results due to differences between machines and improve the reproducibility of the machining dimensions. [Brief description of the drawings]

[0013] [Figure 1] 1 is an explanatory diagram of a change in output pulse width Tout due to a threshold voltage Vth relative to an input peak voltage Vpeak of an electric element T. FIG. [Diagram 2] 1 is a schematic diagram of an electric discharge machining circuit 1 in a wire electric discharge machining apparatus according to an embodiment of the present invention. [Diagram 3] 1 is a schematic diagram of a pulse generating device 50 according to an embodiment of the present invention. [Figure 4] 3 is a schematic diagram of an adjustment voltage pulse waveform output by a pulse generating device 50 according to an embodiment of the present invention. FIG. [Diagram 5] 13 is a diagram showing a source-drain voltage waveform of a switching element 401b of a system SGL. FIG. [Figure 6] FIG. 1 is an explanatory diagram of the mechanism of an adjustment process. [Figure 7] FIG. 2 is a circuit diagram of a gate signal generating circuit 30 used in the measurement. [Figure 8] 13 shows source-drain voltage waveforms before the adjustment process of the system GGL in the substrate X1 and the substrate X2. [Figure 9] 13 shows source-drain voltage waveforms before the adjustment process of the system SGL in the substrate X1 and the substrate X2. [Figure 10] 13 shows no-load inter-contact pulse waveforms before the adjustment process for the substrates X1 and X2. [Figure 11] 13 shows source-drain voltage waveforms after the adjustment process of the system GGL in the substrate X1 and the substrate X2. [Figure 12]13 shows no-load inter-contact pulse waveforms after the adjustment process for the substrates X1 and X2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present invention will be described. Various features shown in the following embodiments can be combined with each other. Also, each feature can be an invention independently.

[0015] 1. Wire Electric Discharge Machining Equipment In wire electric discharge machining, a predetermined voltage pulse is applied to a machining gap formed between a wire provided in a wire electric discharge machining device and a workpiece to generate intermittent electric discharges, and material is removed from the workpiece by electric discharge machining energy, cutting the workpiece into a desired machining shape. The wire electric discharge machining device is equipped with an electric discharge machining circuit 1.

[0016] 2 shows a schematic diagram of an electric discharge machining circuit 1 in a wire electric discharge machining apparatus according to one embodiment of the present invention. The electric discharge machining circuit 1 is a circuit for applying a voltage for generating an electric discharge in a machining gap between a wire and a workpiece. The electric discharge machining circuit 1 may include a pulse generating circuit 10, a communication cable 20, a gate signal generating circuit 30, and a bipolar circuit 40. The electric discharge machining circuit 1 includes four systems SGU, SGL, GGU, and GGL that are respectively connected to switching elements 401a, 401b, 401c, and 401d included in the bipolar circuit 40.

[0017] 1.1 Pulse Generator 10 The pulse generating circuit 10 is a circuit that can output voltage pulses for controlling the switching elements 401a to 401d of the bipolar circuit 40 to the gate signal generating circuit 30 in a differential manner. Specifically, the pulse generating circuit 10 includes an FPGA 101 (Field Programmable Gate Array) for generating discharge pulses and a differential output driver 102. A predetermined voltage pulse generated by the FPGA 101 can be input to each terminal of the differential output driver 102 for each system connected to the switching elements 401a to 401d. In the example of FIG. 2, the system SGU is connected to the switching element 401a, the system SGL is connected to the switching element 401b, the system GGU is connected to the switching element 401c, and the system GGL is connected to the switching element 401d. For example, a voltage pulse can be input to each terminal of the differential output driver 102 so that the switching elements 401a and 401b of the bipolar circuit 40 are driven to have a reverse polarity, and the switching elements 401c and 401d are driven to have a positive polarity.

[0018] The differential output driver 102 is connected to the communication cable 20 and can output a differential voltage pulse to the gate signal generation circuit 30 via the communication cable 20. The differential output can reduce noise. The ferrite core 21 removes noise from the communication cable 20 that is passed through it.

[0019] 1.2 Gate signal generating circuit 30 The gate signal generating circuit 30 is a circuit that can receive differential voltage pulses from the pulse generating circuit 10 as inputs and generate gate signals that drive the switching elements 401a to 401d of the bipolar circuit 40. In the gate signal generating circuit 30 shown in Fig. 2, only the configuration of the SGU system is shown, but the SGU, SGL, GGU, and GGL systems have the same configuration. The symbols of the components included in the SGL, GGU, and GGL systems (not shown) are those in which the suffix "a" of the symbol of the component included in the SGU system is changed to "b" for SGL, "c" for GGU, and "d" for GGL.

[0020] The gate signal generating circuit 30 includes photocouplers 301a, 301b, 301c, and 301d connected to the switching elements 401a, 401b, 401c, and 401d, respectively, and switching drivers 302a, 302b, 302c, and 302d. The photocouplers 301a to 301d are used to transmit signals from the input side to the output side in an electrically insulated state, and receive differential voltage pulses from the pulse generating circuit 10 to output signals to the switching drivers 302a to 302d, respectively. The switching drivers 302a to 302d generate gate signals for driving the switching elements 401a to 401d.

[0021] The signal input paths of the photocouplers 301a to 301d are provided with resistors connected in series. Specifically, a fixed resistor (not shown) and semi-fixed resistors Ra, Rb, Rc, and Rd are provided. The fixed resistors are provided as protective resistors to prevent excessive current from flowing through the photocouplers 301a to 301d. The resistance value of the fixed resistors is preferably about 250 to 300 Ω. The semi-fixed resistors Ra to Rd are provided to change the current value flowing through the photocouplers 301a to 301d by adjusting the resistance value, and to adjust the output voltage waveform of the switching elements 401a to 401d provided in the bipolar circuit 40 or the inter-electrode pulse waveform applied to the wire and the workpiece. A specific adjustment method will be described later.

[0022] 1.3 Bipolar Circuit 40 The bipolar circuit 40 is a bridge circuit in which switching elements 401a to 401d are provided on each side. The switching elements 401a to 401d receive gate signals of different polarities from the gate signal generating circuit 30, and thereby each switching element 401a to 401d is controlled to supply a voltage pulse whose polarity periodically switches (hereinafter, bipolar pulse) to the machining gap between the wire and the workpiece. The switching elements 401a to 401d can be field effect transistors, for example, MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors).

[0023] In the bipolar circuit 40, the connection point of the switching elements 401a and 401c is the input section 402a, and the connection point of the switching elements 401b and 401d is the input section 402b. The connection point of the switching elements 401a and 401d is the output section 403a, and the connection point of the switching elements 401b and 401c is the output section 403b. A DC power source (not shown) is connected to the input sections 402a and 402b, and a DC voltage is applied to the input sections 402a and 402b. The output sections 403a and 403b are connected to the wire and the workpiece, respectively. The switching elements 401a to 401d are controlled to be turned on and off by the above-mentioned gate signal, so that a bipolar pulse is output from the output sections 403a and 403b, and a voltage is applied to the machining gap, enabling machining.

[0024] 2. Pulse Generator 50 The pulse generating device 50 is an external device independent of the wire electric discharge machining apparatus, and functions as a checker for adjusting the voltage pulse output from the electric discharge machining circuit 1 in the manufacturing process of the electric discharge machining apparatus. A schematic diagram of the pulse generating device 50 is shown in Fig. 3. The pulse generating device 50 is configured to be connectable to the gate signal generating circuit 30 of the electric discharge machining circuit 1.

[0025] The pulse generating device 50 can have the same configuration as the pulse generating circuit 10. Specifically, the pulse generating device 50 includes an FPGA 501 for generating a discharge pulse and a differential output driver 502. A predetermined adjustment voltage pulse generated by the FPGA 501 can be input to each terminal of the differential output driver 502 for each system. In the example of Fig. 3, the system SGU is connected to the switching element 401a, the system SGL is connected to the switching element 401b, the system GGU is connected to the switching element 401c, and the system GGL is connected to the switching element 401d.

[0026] The differential output driver 502 can output four patterns of adjustment voltage pulses (differential voltage pulses) to the switching elements 401a to 401d included in the gate signal generation circuit 30. Fig. 4 shows an example of an adjustment voltage pulse waveform that the pulse generation device 50 outputs to each system.

[0027] 3. Manufacturing method of wire electric discharge machining device The manufacturing method of the electric discharge machining device includes an adjustment step and an assembly step.

[0028] 3.1 Adjustment process The adjustment step is to adjust the pulse width T out The adjustment step can be performed after a substrate X having the gate signal generating circuit 30 and the bipolar circuit 40 in the electric discharge machining circuit 1 is fabricated, while an adjustment voltage pulse is being supplied to the substrate X by an external pulse generating device 50 that is independent of the electric discharge machining device.

[0029] In the adjustment process, first, the substrate X is connected to the pulse generating device 50. Next, the pulse generating device 50 inputs adjustment voltage pulses of four patterns corresponding to the respective systems to the gate signal generating circuit 30. At that time, the pulse width T out The resistance values ​​of the semi-fixed resistors Ra to Rd are adjusted so that the resistance falls within a specified range. If the resistance values ​​of the semi-fixed resistors Ra to Rd are made too small, the ferrite core 21 provided in the communication cable 20 may generate heat. Therefore, it is preferable that the resistance values ​​of the semi-fixed resistors Ra to Rd are adjusted to be in a range of 300 Ω or more.

[0030] The pulse width T of the output voltage waveform of the switching elements 401a to 401d out corresponds to the pulse width of the source-drain voltage waveform of the switching elements 401a to 401d when an adjustment voltage pulse is supplied by the pulse generating device 50. FIG. 5 is an example of a diagram showing a source-drain voltage waveform of the switching element 401b of the system SGL. The pulse width T out The prescribed range can be, for example, 36 to 38 ns.

[0031] In a wire electric discharge machining apparatus using high frequency pulses, the threshold voltage V of various electric elements provided in the electric discharge machining circuit 1 is thEach time it passes through the electrical element, the pulse width T out Also, the threshold voltage V th Due to individual differences, the pulse width of the inter-machine pulse differs for each device, resulting in machine differences in the machining results.

[0032] 6 is an exemplary explanatory diagram of the mechanism of the adjustment process according to the present invention. In FIG. 6, the pulse width T in When the pulse width T of the output voltage pulse of the switching elements 401a to 401d is 100 ns, out The voltage pulse that passes through the photocouplers 301a to 301d changes in comparison with the initial pulse of the previous stage. The amount of this change is the threshold voltage V th Here, by changing the resistance value of the semi-fixed resistors Ra to Rd, the slope of the input voltage rise can be changed. As a result, the threshold voltage V th It is possible to change the minute time it takes for the voltage pulse to rise to the threshold voltage V th The change in the small amount of time until the pulse passes through the resistors Ra to Rd is expressed as the pulse width T out You can adjust it.

[0033] In the same manner, the initial pulse is generated by the threshold voltage V of the other electric elements present in the transmission path of the electric discharge machining circuit 1. th The cumulative pulse width T out The pulse width T changes depending on the resistance of the semi-fixed resistors Ra to Rd. out The adjustment margin is the pulse width T out That is, in FIG. 6, the pulse width T outIf the resistance of the resistors Ra to Rd is adjusted to 40ns and the target value is 50ns, and the adjustment margin is 20ns, the pulse width T out It is possible to adjust the delay to 50ns.

[0034] In this adjustment process, the pulse width T out By adjusting to be within the specified range, the threshold voltage V th This adjustment process allows for high-precision machining using high-frequency pulses, while at the same time making the electric discharge machining energy by each electric discharge machining device uniform and improving the reproducibility of the machining dimensions. In this specification, high precision refers to high precision in the machining dimensions and fine surface roughness of the machined surface.

[0035] In wire electric discharge machining equipment using high frequency pulses, the pulse width T out The magnitude of the high frequency amplitude W1, W2 (the high frequency amplitude on the positive polarity side is W1, and the high frequency amplitude on the reverse polarity side is W2) of the no-load inter-electrode pulse waveform in the final stage can be evaluated. For example, the electric discharge machining circuit 1 is configured to be able to adjust the high frequency amplitude W1 by changing the resistance value of the semi-fixed resistor Rb included in the gate signal generating circuit 30 connected to the switching element 401b of the system SGL. Also, for example, the high frequency amplitude W2 is configured to be able to adjust the high frequency amplitude W2 by changing the resistance value of the semi-fixed resistor Rd included in the gate signal generating circuit 30 connected to the switching element 401d of the system GGL. For example, it is preferable that the high frequency amplitudes W1, W2 are within ±3V of the specified value. In the experiment described later, the values ​​of the high frequency amplitudes W1, W2 were also used to evaluate this adjustment process.

[0036] 3.2 Installation process The installation process is a process of installing the substrate X in the wire electric discharge machining apparatus after the adjustment process. Specifically, the substrate X is installed so as to be connectable to the pulse generating circuit 10 of the electric discharge machining circuit 1 of the electric discharge machining apparatus and the gate signal generating circuit 30 via the communication cable 20.

[0037] 4. Other embodiments The adjustment step may be performed by the pulse generating circuit 10 included in the electric discharge machining circuit 1 instead of the pulse generating device 50. The adjustment step in this embodiment is performed after the pulse generating circuit 10, the gate signal generating circuit 30, and the bipolar circuit 40 are connected, and can be performed in a state in which the adjustment voltage pulse, which is a differential voltage pulse generated by the pulse generating circuit 10, is supplied to the substrate X.

[0038] 5. Working Example Specific experimental results obtained by carrying out the adjustment process will be described below.

[0039] 5.1 Overview Using two boards X1 and X2, the resistance values ​​of variable resistors R64 and R73 provided in the signal input paths of photocouplers 301b and 301d provided in the gate signal generating circuits 30 of the boards X1 and X2 were adjusted to individually correct the pulse widths of the source-drain voltage waveforms of the switching elements 401b and 401d. After that, the no-load inter-electrode pulse waveforms, which are the final stage of the electric discharge machining circuit 1 used in actual machining, were compared.

[0040] 5.2 Measurement method 7 shows a circuit diagram of the gate signal generating circuit 30 of the system in which the adjustment process was carried out in this experiment. In this experiment, adjustment voltage pulses were generated by the pulse generating circuit 10 using the boards X1 and X2 each including the gate signal generating circuit 30 and the bipolar circuit 40. The resistance values ​​of the variable resistors R64 and R73 of the gate signal generating circuits 30 of the system GGL and system SGL were changed to adjust the pulse width T outThe period was adjusted to be around 37 ns. The waveform of the no-load inter-contact pulse when the adjustment process was performed was also measured. MOSFETs were used for the switching elements 401b and 401d. The source-drain voltage waveforms and the no-load inter-contact pulse waveforms of the switching elements 401b and 401d were measured using an oscilloscope.

[0041] Figure 8 shows the source-drain voltage waveforms in the system GGL of the substrates X1 and X2 before the adjustment process is performed. Figure 9 shows the source-drain voltage waveforms in the system SGL of the substrates X1 and X2 before the adjustment process is performed. Figure 10 shows the no-load inter-contact pulse waveforms in the substrates X1 and X2 before the adjustment process is performed.

[0042] As shown in Fig. 9, the pulse width T out The high frequency amplitude W1 of the no-load inter-electrode pulse waveform was 90.0 V for the board X1 and 87.0 V for the board X2, both within the allowable range of the target value of 90 V for the high frequency amplitude W1. Therefore, the resistance value of the variable resistor R73 was not adjusted, and only the resistance value of the variable resistor R64 provided in the system GGL was changed.

[0043] 5.3 Measurement results FIG. 11 shows the source-drain voltage waveforms after the adjustment process is performed in the system GGL of the boards X1 and X2. FIG. 12 shows the no-load inter-contact pulse waveforms after the adjustment process is performed on the boards X1 and X2. Table 1 shows the pulse width T out and the high frequency amplitude W2 of the no-load inter-contact pulse waveform. [Table 1]

[0044] Through the adjustment process, the pulse width T outwas able to be adjusted to within the allowable range of 37 ns (36 to 38 ns). The high frequency amplitude W2 of the no-load inter-contact pulse waveform was also able to be adjusted to a value of about 90 V. Therefore, it was found that the source-drain voltage waveforms of substrates X1 and X2 and the no-load inter-contact pulse waveform could be adjusted to close values, and that by carrying out the adjustment process, machine differences in the waveforms could be corrected. [Explanation of symbols]

[0045] 1: Electrical discharge machining circuit 10: Pulse generation circuit 101: FPGA 102: Differential output driver 20: Communication cable 21: Ferrite core 30: Gate signal generation circuit 301a~301d: Photocouplers 302a to 302d: switching drivers 40: Bipolar circuit 401a to 401d: switching elements 402a, 402b: Input section 403a, 403b: Output section 50: Pulse generator 501: FPGA 502: Differential output driver A1, A2: Peak voltage value Ra~Rd: Semi-fixed resistor T: Electrical element T in : Input pulse width T out : Output pulse width T Rout : Reference output pulse width V peak : Input peak voltage V th : Threshold voltage V Rth : Reference threshold voltage W1: High frequency amplitude W2: High frequency amplitude X, X1, X2: Circuit board

Claims

1. A method for manufacturing a wire electric discharge machining device including a pulse generating circuit, a gate signal generating circuit, and a bipolar circuit, comprising: the pulse generating circuit differentially outputs a voltage pulse for controlling a switching element of the bipolar circuit to the gate signal generating circuit; the gate signal generation circuit includes a photocoupler and a switching driver, the photocoupler receives a differential voltage pulse from the pulse generation circuit and outputs the differential voltage pulse to the switching driver, and the switching driver generates a gate signal for driving the switching element; The bipolar circuit is a bridge circuit in which the switching element is provided on each side, and the switching element is controlled by receiving the gate signal to supply a machining gap voltage pulse whose polarity periodically switches to the machining gap between the wire and the workpiece; The photocoupler includes a resistor in a signal input path, The manufacturing method includes an adjusting step, In the adjusting step, an output voltage waveform of the switching element is adjusted by changing a resistance value of the resistor when an adjustment voltage pulse generated by the pulse generating circuit or an external pulse generating device is supplied to the gate signal generating circuit. A method for manufacturing a wire electric discharge machining device.

2. A method for manufacturing the wire electric discharge machining device according to claim 1, the adjusting step is performed in a state in which a substrate having the gate signal generating circuit and the bipolar circuit is supplied with the adjusting voltage pulse by the external pulse generating device independent of the wire electric discharge machining apparatus; an assembling step of assembling the substrate into the wire electric discharge machining apparatus after the adjusting step; A method for manufacturing a wire electric discharge machining device.

3. A method for manufacturing the wire electric discharge machining device according to claim 1 or 2, comprising the steps of: the switching element is a field effect transistor, In the adjusting step, a pulse width of a voltage waveform between a source and a drain of the field effect transistor is set within a predetermined range.

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